1. Field of the Invention
The present invention relates to a method of manufacturing heat insulating structural elements and/or light elements composed of at least two wall elements of glass, a glass alloy or metal separated from each other by support elements, wherein the wall elements have on at least one of the surfaces facing each other a heat radiation-reflecting layer; the structural and/or light elements further are composed of a deformable sealing element attached to the edges of the wall elements and connected to the wall elements to form a hollow space which can be evacuated or filled with gas.
2. Description of the Related Art
High insulation values make it possible to construct and utilize structures and insulations in an energy-saving and an environment-protecting manner. Insulation technology had a great significance not only since the climate conferences in which the member countries pledged to reduce their energy consumption and the CO2 output.
Consequently, it is necessary to reduce the heat transmission coefficient or K-coefficient in especially affected windows, windows, window-like doors and roof windows as well as other structural and light elements. However, such high insulation requirements cannot be met by conventional insulating glass and the method used for manufacturing the glass.
By comparison, the outer walls of a building can be constructed with a K-coefficient of 0.2 W/m2xc2x0 K; however, the windows are far away from reaching such values and, therefore, are also called cold holes.
As is well known, windows, for example, windows with two or more panes, are manufactured by removing or cleaning foreign bodies or dirt from the surfaces of the individual panes in a noble gas atmosphere by means of cathodes which produce a combustion, and the cleaned surfaces are then coated with an infrared coating under similar ambient conditions. The infrared or low-E layer serves to prevent the heat transmission.
The coating is applied by magnetron sputtering in an evacuated tunnel having a length of about 50 m; accordingly, a large amount of energy and high technical and financial requirements are necessary.
At the end of the coating process, the glass panes are removed from the evacuated tunnel and are further processed in an atmospheric surrounding into gas-filled light elements or windows.
These complicated and expensive treatments have in the past been used exclusively for cleaning and coating the surfaces of glass panes used for windows. In this connection, reference is being made to an essay by Dr.-Ing. H. Christian Schaefer in xe2x80x9cVakuum in Forschung und Praxis [Vacuum in Research and Practice] (1995) No. 3xe2x80x9d The author points out that in accordance with a heat protection decree, each insulating glass must have a heat insulating layer in order to come closer to the requirements of an improved insulation.
However, the measures mentioned above are not sufficient for making it possible to achieve a significant reduction of the K-coefficient to about 0.3 W/m2xc2x0 K. On the contrary, further efforts are required in practice to be able to realize a mechanical insulation for manufacturing such insulation layers in an economical manner.
Because of the new findings, the required high energy consumption and the necessary financial investments no longer justify a manufacture of structural and/or light elements in accordance with the known methods.
The insulation technology utilized in the past for windows and facades is now outdated for several years, however, further innovations are intentionally suppressed.
It is only a structural and/or light element according to EP-A-0 247 098, which makes possible a K-coefficient of less than 0.4 W/m2xc2x0 K, that a further development of an economically interesting manufacture of structural and/or light elements can be carried out under rational and successful conditions.
Therefore, starting from the prior art discussed above, it is the primary object of the present invention to manufacture in an economical manner structural and/or light elements of the above-described type with high insulation values which have not been achieved in the past, and to use these elements in new buildings as well as in existing buildings and installations.
In accordance with the present invention, the wall elements pretreated for a structural and/or light element are guided in a manufacturing procedure over manufacturing sections, wherein the edges of each wall element are coated with solder on at least one side thereof, support elements are placed spaced apart on a wall element, subsequently the wall elements are positioned opposite each other while maintaining a distance determined by the support elements, and the wall elements are enclosed to form a gas-tight hollow space by means of a deformable metal sealing element attached to the coated edges of the two wall elements.
The method according to the invention makes possible an economical manufacture of structural and/or light elements constructed as windows, roof elements or facade elements, also for greenhouses, with a K-coefficient which is lower than any achieved in the past.
In accordance with an alternative embodiment, the solder layer can also be attached to a wall element after the support elements have been mounted on the wall element.
In accordance with an advantageous feature, the wall elements intended for a structural and/or light element to be provided with an evacuated hollow space travel through a room which can be separated into at least one manufacturing chamber which can be evacuated and is equipped in accordance with a certain manufacturing method, so that it is possible to adjust optimum conditions for the manufacturing method taking place in this room.
For achieving an economical manner of operation, the wall elements used for a structural and/or light element are moved through the manufacturing sections one behind the other, next to other, above each other, staggered next to or above each other.
Since the method according to the invention requires a high degree of automation for manufacturing the structural and/or light elements, it is advantageous to construct the manufacturing sections provided for manufacturing procedures as manufacturing rooms, wherein the manufacturing rooms are provided with a vacuum adjusted to the manufacturing method to be carried out in the room.
The previously known cleaning of the wall elements and the subsequent application of a heat reflecting layer under vacuum in a so called flat glass coating plant could be carried out prior to the method of the invention and the two methods could be combined in a manufacturing sequence. This would make it possible to continue to operate existing flat glass coating plants (about 40 in Europe) together with the method of the invention. By connecting the flat glass coating plant and the method according to the invention, the structural and/or light element can be constructed in a simple manner with a significantly more efficient cleaning effect and with a higher quality of the infrared layer. This technical as well as economic advantage makes it unnecessary to heat the pretreated or infrared layer-coated wall elements at a temperature of about 400xc2x0 C. for removing the water skins which form within the shortest time in an atmospheric surrounding. A coating would not survive such a measure undamaged and, in the case of an evacuation, such a measure would lead to a continuous high gas discharge rate.
When a pretreatment section for cleaning and coating the wall elements with a heat radiation reflecting layer is provided it is advantageous if a conveying and manufacturing connection is provided between the pretreatment section and the subsequent manufacturing section for carrying out the method according to the invention.
The pretreatment section in the form of at least evacuatable manufacturing section in which the wall elements are cleaned and/or provided with an infrared layer or low E-layer, can also be arranged perpendicularly relative to the installation according to the present invention, such that the conveying direction used for pretreating the wall elements extends at a right angle relative to the conveying direction of the installation according to the invention and ends at the beginning of the latter. When the infrared-coated wall elements are further processed into structural and/or light elements, they deflected by about 90 degrees into the conveying direction of the insulation of the invention without leaving the evacuated surrounding.
However, if the wall elements are exclusively provided with an infrared layer, they can be removed from the flat glass coating section or pretreatment section in the conveying direction of this pretreatment section. In other words, the method and/or installation according to the present invention could be combined with an existing flat glass coating plant and could be universally operated as a result and the efficiency and output could be markedly improved.
Because of the different manufacturing methods, the manufacturing sections are advantageously constructed as manufacturing rooms.
In order to optimize and adapt the manufacturing rooms to the manufacturing methods, it is important for achieving an economical manufacture of the structural and/or light elements that the manufacturing rooms which can be evacuated can be constructed so as to be separable from each other, so that each manufacturing section determined for a manufacturing method to be carried out can be utilized in an optimum manner.
The manufacturing rooms are arranged particularly advantageously if, after the wall elements have been cleaned and/or provided with a heat radiation-reflecting layer and immediately subsequently the edge coatings for later attaching the edge sealing element have been applied to the wall elements, at least two one of the wall elements are transferred the support elements required for the spacing of the wall elements in a distributed configuration, subsequently the wall elements are positioned relative to each other at the distance of the transferred support elements, and subsequently the wall elements are enclosed with the resilient metal edge sealing elements so as to form a hollow space which is evacuated or can be evacuated. This manner of operation makes it possible to carry out the individual manufacturing steps continuously and in a simple manner to carry out the manufacturing method according to the present invention.
For achieving an optimum connection of the wall elements at the edges by means of the sealinq element by utilizing the evacuatable manufacturing rooms, it is advantageous to carry out the coating of the edges by means of physical or chemical separation of the material from the gas or vapor phase, as described, for example in EP-A-0 434 802.
Because of the high energy quantities required for producing the vacuum, it is recommended that the evacuated manufacturing sections are constructed so that they can be separated from each other when manufacturing interruptions occur.
The manufacturing sections can be constructed in such a way that the wall elements travel therethrough vertically or horizontally, so that the manufacturing rooms and the devices provided therein can be used in an optimum manner.
An installation for carrying out the method includes a conveying device for transporting the wall elements on a manufacturing line composed of several manufacturing sections, wherein at least portions of the conveying device are connected to a vacuum source for forming a vacuum environment, and wherein appropriate manufacturing devices are provided for the manufacturing sections.
The manufacturing sections are advantageously constructed for forming an edge coating at the wall elements, for placing support elements on the wall elements, for joining at least two wall elements together and for mounting a deformable metal sealing element at the edges of the joined wall elements, wherein this or another sequence may be used, so that a problem-free manufacturing process can be carried out.
For effecting a direct connection between the manufacturing rooms, the passage openings are provided as in the prior art with closing flaps or slides, so that the pressureless condition can be cancelled in individual manufacturing rooms and access to the installed manufacturing devices is possible.
The possibility of combining the installation according to the invention with an existing flat glass coating plant has already been described above; however, it must additionally taken into consideration that the combination between the plants requires a connection which can be evacuated; this does not require any special features because the coating section of the flat glass coating plant is already constructed so that it can be evacuated.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of the disclosure. For a better understanding of the invention, its operating advantages, specific objects attained by its use, reference should be had to the drawing and descriptive matter in which there are illustrated and described preferred embodiments of the invention.